The present invention relates to a glow plug used in a diesel engine or the like, and in particular, to further improvement of the reliability of a glow plug and a vehicle based on providing a new glow plug, which can be easily determined as to whether or not it is a new article at the time of replacement, and providing a new article determination method.
The quality of a glow plug used in a diesel engine or the like may have a large influence on a startup of a diesel engine or the like. For this reason, various devices for detecting the deterioration have been proposed and put to practical use up to now. For example, a method of determining the presence or absence of deterioration on the basis of a change in the resistance of a heater has been proposed (for example, refer to JP-A-2009-191842).
Incidentally, it cannot be determined at a glance whether or not a glow plug is a new article, in many cases, due to its structure. Therefore, for some reason at the time of replacement or the like, there is a possibility that a deteriorated article will be erroneously mounted as a new article.
However, conventionally, there has been no method or device capable of reliably and relatively easily determining whether or not a glow plug is a new article.
For example, although there is a method of determining the presence or absence of deterioration on the basis of the amount of change in the resistance as described above, this method cannot be applied as it is for determination regarding whether or not a glow plug is a new article. That is, with only the amount of change in the resistance, it is determined that there is no deterioration if the amount of change satisfies the specification of so-called on-board diagnostics (OBD) which is a self-diagnostic function system of the vehicle. Eventually, it is not possible to determine whether or not a glow plug is a new article.